And while he has never won a major when trailing going into the last day, the outlook didn't look bleak from his vantage point.
"I'm only two back," Woods said. "There's only one guy ahead of me."
Instead of playing with Westwood in the final group, Woods will be in the penultimate group with Masters champion Adam Scott, who had a 70. The Australian not only is poised to be the first player with a multiple-major season in seven years, he can atone for his meltdown a year ago at Royal Lytham & St. Annes.
"I go out there tomorrow not carrying the weight of the lead or not having won a major," Scott said. "So it's a different feeling."
Mahan made only two bogeys, and he avoided a third on the final hole when he made a 25-foot putt to save par from the bunker. He played with Mickelson in the final round at Merion and stayed in the game until late in the round, closing with a 75. One month later, he gets another crack at it.
And there are plenty of others still in the game — five major champions within five shots of the lead, a list that goes down to Mickelson at five shots behind.
Two-time major champion Angel Cabrera opened with 12 pars and had a roller-coaster finish — double bogey, birdie, bogey — for a 73. He was at 1-over 214, along with former Masters champion Zach Johnson (73), Henrik Stenson (74) and Ryan Moore (72).
But it starts with Westwood, who can add to the British celebration of sport by capturing his first major. He certainly looked up to the task over 18 holes in the third round, and he didn't seem the least bit uptight when asked to think about what was at stake Sunday.
"I'm not in a high-pressure situation because I'm going to go have dinner, and I'm so good with a knife and fork now that I don't feel any pressure at all," he said, trying to keep the mood light.
He sees nothing wrong with imagining his name on the base of the claret jug, ending all those questions about whether he has the game and guts to win a major. But when he steps to the first tee Sunday, it's all about finding the short, yellow grass carved out of rough that looks like a Kansas wheat field.
"I should be in the same frame of mind as I was today," Westwood said. "I didn't feel any pressure today — felt nice and calm out there and in control of what I was doing."
Miguel Angel Jimenez didn't lose control. He just lost the lead.
The 49-year-old Spaniard found too many bunkers, missed too many fairways and dropped far too many shots. He wound up with a 77, six shots behind.
Woods was never far from the lead, even during four two-shot swings involving Westwood.
The first one came on the par-5 fifth hole. Woods proved there was a driver under that tiger head cover by smashing his tee shot down the fairway, though he wound up missing a 6-foot birdie putt, while Westwood rolled in a 50-foot eagle putt from just short of the green.
Westwood hit a high shot that settled 4 feet from the cup at the par-3 seventh while Woods hammered a 9-iron through the green and made bogey. Westwood led by as many as three shots, but they were tied at the turn when Westwood found a bunker of the tee and made bogey, while Woods had a simple up-and-down for birdie.
The last three holes changed everything — a bogey that could have been much worse, a birdie to build a cushion, a par for confidence.